According to the interim Geneva nuclear agreement signed last November, Iran had to take steps to alleviate the concerns of the world powers over its nuclear programme in exchange for partial lifting of economic sanctions posed by the West.

There has been multiple rounds of negotiations between Iran and the P5+1 group -- the five permanent members of the UN Security Council plus Germany -- but the leaders could not come to any conclusions and talks for a final deal were stalled as the two sides are still far apart on some core issues, such as Iran's future enrichment capacity.